feat(mq-starter-core): 启动期校验 mq.type 有对应 MqDriver（③ fail-fast）

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

mq-starter-core/src/main/java/com/njcn/mq/autoconfig/MqDriverPresenceAutoConfiguration.java

@@ -0,0 +1,51 @@
+package com.njcn.mq.autoconfig;
+
+import com.njcn.mq.spi.MqDriver;
+import org.springframework.beans.factory.ObjectProvider;
+import org.springframework.beans.factory.SmartInitializingSingleton;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.env.Environment;
+
+/**
+ * ③ 通用校验：显式配了 {@code mq.type}，却没有装配任何 {@link MqDriver}，
+ * 说明忘引对应 starter 或 mq.type 拼错 —— 启动失败并给中文提示。
+ *
+ * <p>为何“有没有 MqDriver”就够：两个 driver 的 AutoConfiguration 都用
+ * {@code @ConditionalOnProperty(name="mq.type", havingValue=...)} 按 mq.type 条件装配，
+ * 因此“存在 MqDriver bean”已等价于“配的 mq.type 有对应 driver”。
+ *
+ * <p>仅当显式配了 {@code mq.type} 时装配；没配则完全不介入（存量零影响）。
+ * 放在 core 是因为：redis/rocketmq 包没引入时其模块内的类自己都不加载，无法自证缺失；
+ * 只有 core 有“到底有没有 MqDriver”的全局视角。
+ */
+@Configuration
+@ConditionalOnProperty(name = "mq.type")
+public class MqDriverPresenceAutoConfiguration implements SmartInitializingSingleton {
+
+    private final ObjectProvider<MqDriver> drivers;
+    private final Environment env;
+
+    public MqDriverPresenceAutoConfiguration(ObjectProvider<MqDriver> drivers, Environment env) {
+        this.drivers = drivers;
+        this.env = env;
+    }
+
+    @Override
+    public void afterSingletonsInstantiated() {
+        if (!MqStartupChecks.enabled(env)) {
+            return;
+        }
+        String configured = env.getProperty("mq.type");
+        // 用 stream() 而非 getIfAvailable()：同时引多个 driver 包时不会抛 NoUniqueBeanDefinitionException
+        if (drivers.stream().findAny().isPresent()) {
+            return; // 有 driver 装配，放行
+        }
+        throw new IllegalStateException(
+                "MQ 启动失败：已配置 mq.type=" + configured + "，但没有装配任何 MqDriver。\n"
+                + "请检查：\n"
+                + "  1) 是否引入对应 starter 依赖（redis-stream 需 mq-starter-redis-stream + spring-boot-starter-data-redis；\n"
+                + "     rocketmq 需 mq-starter-rocketmq + rocketmq starter）；\n"
+                + "  2) mq.type 是否拼写正确（支持：redis-stream / rocketmq）。");
+    }
+}

mq-starter-core/src/main/java/com/njcn/mq/autoconfig/MqStartupChecks.java

@@ -0,0 +1,16 @@
+package com.njcn.mq.autoconfig;
+
+import org.springframework.core.env.Environment;
+
+/** MQ 启动校验的公共工具：统一读取逃生开关 {@code mq.startup-check.enabled}（默认 true）。 */
+public final class MqStartupChecks {
+
+    private MqStartupChecks() {
+    }
+
+    /** @return true 表示应执行启动校验；false 表示使用者主动关闭。 */
+    public static boolean enabled(Environment env) {
+        return Boolean.TRUE.equals(
+                env.getProperty("mq.startup-check.enabled", Boolean.class, Boolean.TRUE));
+    }
+}

mq-starter-core/src/main/resources/META-INF/spring.factories

@@ -1,2 +1,3 @@
 org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
-com.njcn.mq.autoconfig.MqCoreAutoConfiguration
+com.njcn.mq.autoconfig.MqCoreAutoConfiguration,\
+com.njcn.mq.autoconfig.MqDriverPresenceAutoConfiguration

mq-starter-core/src/test/java/com/njcn/mq/autoconfig/MqDriverPresenceAutoConfigurationTest.java

@@ -0,0 +1,42 @@
+package com.njcn.mq.autoconfig;
+
+import com.njcn.mq.spi.MqDriver;
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.test.context.runner.ApplicationContextRunner;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+
+class MqDriverPresenceAutoConfigurationTest {
+
+    private final ApplicationContextRunner runner = new ApplicationContextRunner()
+            .withConfiguration(AutoConfigurations.of(MqDriverPresenceAutoConfiguration.class));
+
+    @Test
+    void noMqType_doesNotFail() {
+        runner.run(ctx -> assertThat(ctx).hasNotFailed());
+    }
+
+    @Test
+    void mqTypeButNoDriver_fails() {
+        runner.withPropertyValues("mq.type=redis-stream")
+                .run(ctx -> {
+                    assertThat(ctx).hasFailed();
+                    assertThat(ctx).getFailure().hasMessageContaining("redis-stream");
+                });
+    }
+
+    @Test
+    void mqTypeWithDriver_ok() {
+        runner.withPropertyValues("mq.type=redis-stream")
+                .withBean("someDriver", MqDriver.class, () -> mock(MqDriver.class))
+                .run(ctx -> assertThat(ctx).hasNotFailed());
+    }
+
+    @Test
+    void disabled_skipsCheck() {
+        runner.withPropertyValues("mq.type=redis-stream", "mq.startup-check.enabled=false")
+                .run(ctx -> assertThat(ctx).hasNotFailed());
+    }
+}